Merge branch 'zj-kamil-slack-slash-commands' into 'master'

Slack slash commands

## What does this MR do?

Implement Slack Slash Commands by utilizing generalized Mattermost presenter to fulfill Slack requirements.

## Why was this MR needed?

We want to expose Slack Slash Commands as a first-class service.

## What are the relevant issue numbers?

Supersedes !8007  
Closes #22182

See merge request !8126

2 files changed, 43 insertions, 3 deletions

diff --git a/spec/features/admin/admin_settings_spec.rb b/spec/features/admin/admin_settings_spec.rb
index 8cd66f189be..47fa2f14307 100644
--- a/spec/features/admin/admin_settings_spec.rb
+++ b/spec/features/admin/admin_settings_spec.rb
@@ -17,9 +17,9 @@ feature 'Admin updates settings', feature: true do
     expect(page).to have_content "Application settings saved successfully"
   end
 
-  scenario 'Change Slack Service template settings' do
+  scenario 'Change Slack Notifications Service template settings' do
     click_link 'Service Templates'
-    click_link 'Slack'
+    click_link 'Slack notifications'
     fill_in 'Webhook', with: 'http://localhost'
     fill_in 'Username', with: 'test_user'
     fill_in 'service_push_channel', with: '#test_channel'
@@ -30,7 +30,7 @@ feature 'Admin updates settings', feature: true do
 
     expect(page).to have_content 'Application settings saved successfully'
 
-    click_link 'Slack'
+    click_link 'Slack notifications'
 
     page.all('input[type=checkbox]').each do |checkbox|
       expect(checkbox).to be_checked
diff --git a/spec/features/projects/services/slack_slash_command_spec.rb b/spec/features/projects/services/slack_slash_command_spec.rb
new file mode 100644
index 00000000000..32b32f7ae8e
--- /dev/null
+++ b/spec/features/projects/services/slack_slash_command_spec.rb
@@ -0,0 +1,40 @@
+require 'spec_helper'
+
+feature 'Slack slash commands', feature: true do
+  include WaitForAjax
+
+  given(:user) { create(:user) }
+  given(:project) { create(:project) }
+  given(:service) { project.create_slack_slash_commands_service }
+
+  background do
+    project.team << [user, :master]
+    login_as(user)
+  end
+
+  scenario 'user visits the slack slash command config page and shows a help message', js: true do
+    visit edit_namespace_project_service_path(project.namespace, project, service)
+
+    wait_for_ajax
+
+    expect(page).to have_content('This service allows GitLab users to perform common')
+  end
+
+  scenario 'shows the token after saving' do
+    visit edit_namespace_project_service_path(project.namespace, project, service)
+
+    fill_in 'service_token', with: 'token'
+    click_on 'Save'
+
+    value = find_field('service_token').value
+
+    expect(value).to eq('token')
+  end
+
+  scenario 'shows the correct trigger url' do
+    visit edit_namespace_project_service_path(project.namespace, project, service)
+
+    value = find_field('url').value
+    expect(value).to match("api/v3/projects/#{project.id}/services/slack_slash_commands/trigger")
+  end
+end